Evacuable container having one-way valve with filter element

ABSTRACT

A one-way valve allows air to be drawn from a collapsible, flexible, air-tight bag using a vacuum source. When the vacuum source is removed, the one-way valve prevents air from reentering the bag. A filter is placed on the valve body to prevent small particles from the bag from clogging the valve or the vacuum source.

RELATED APPLICATIONS

[0001] This application is a divisional of application Ser. No.09/310,468, filed 12 May 1999 and incorporated herein by reference,which is a continuation-in-part of application Ser. No. 08/851,361,filed 5 May 1997, now issued as U.S. Pat. No. 5,931,189 which is acontinuation of application Ser. No. 08/423,761, filed 17 Apr. 1995,which is a divisional of application Ser. No. 087168,963 filed 15 Dec.1993, now issued as U.S. Pat. No. 5,480,030.

FIELD OF THE INVENTION

[0002] The present invention relates to evacuable storage containers,and in particular to filters for one-way valves used in such storagecontainers.

BACKGROUND

[0003] Collapsible, evacuable storage containers typically include aflexible, air-tight bag, an opening through which to place an article inthe bag, and a fixture through which to evacuate excess air. A userplaces an article into the bag through the opening, seals the opening,and then evacuates the air in the bag through the fixture. With the bagthus evacuated, the article contained therein may be significantlycompressed so that it is easier to transport and requires substantiallyless storage space.

[0004] Collapsible, evacuable storage containers are beneficial forreasons in addition to those associated with compression of the storedarticle. For example, removal of the air from the storage containerinhibits the growth of destructive organisms, such as moths, silverfish,and bacteria, which require oxygen to survive and propagate. Moreover,such containers, being impervious to moisture, inhibit the growth ofmildew.

[0005] Not only large, compressible items such as clothing may be storedin a collapsible, evacuable storage container. For example, it may bedesirable to store bulk items made of small particles, such as powdersor granulated resins, in an evacuated container. One situation thatcommonly occurs is that a particular bulk item is shipped in a large,rigid container such as a drum. Bulk items may be moisture sensitive andare sealed against moisture during shipment. But many times a user doesnot need to use the entire contents of the large container, and so onceexposed to air the remaining bulk contents quickly become unusable andare thus wasted.

[0006] One collapsible, reusable, evacuable storage container is shownin the above-referenced U.S. Pat. No. 5,480,030 issued to Sweeney etal., under common ownership with the present invention, and incorporatedherein by reference in its entirety. The '030 patent discloses a one-wayair valve assembly having a flexible diaphragm that seals against avalve seat. The valve assembly also has vanes positioned to prevent thebag material or bag contents from obstructing air holes or the diaphragmwhile air is being evacuated through the valve assembly. These vanes mayprotect against the bag material, or against large objects stored in thebag, but the vanes do not prevent small particles from entering the airholes and either blocking air holes or preventing the diaphragm fromproperly closing once evacuation is complete. Furthermore, smallparticles may be carried through the valve and become lodged in thevacuum producing device used to evacuate the storage container, thusaffecting operation of the vacuum producing device.

[0007] Therefore the need exists for a reusable, collapsible, evacuablestorage container that may store bulk items that include particles orgranules.

SUMMARY

[0008] Embodiments of the invention are directed to collapsible,evacuable storage containers. These storage containers have a one-wayvalve assembly allowing air to pass out of a flexible, air-tight bag,but not to return to the bag through the valve assembly. A filter isconfigured to be fitted against the one-way valve assembly so thatmaterial in the bag does not pass into or through the valve assemblywhen air is evacuated from the bag.

[0009] In one embodiment of the invention, the filter is made to becompatible with an existing one-way valve assembly. A filter assembly isformed of a cylinder capped by a top portion. The top portion has airslots through which air passes before entering the one-way valveassembly. A filter element is placed in the filter assembly so that airpassing through the air slots is filtered. Embodiments of the inventionmay include filter elements providing filtration for various particulatesizes.

[0010] In an embodiment of the invention, the cylinder of the filterassembly contains a plurality of slots so that the filter assembly maybe placed over radial vanes on the valve body. These slots are formed sothat when the filter assembly is pressed onto the valve assembly, a sealis formed bet ween the filter assembly and the vanes. In one embodimentof the invention, an annular lip is positioned at the base of thecylinder. This lip is configured to seal the filter assembly against acorresponding inner wall of the valve assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011]FIG. 1 is a perspective view of an embodiment of the invention.

[0012]FIG. 2 is a perspective view of a flexible bag.

[0013]FIG. 3 is an exploded perspective view showing an embodiment of avalve assembly and of a filter assembly.

[0014]FIG. 4 is a plan view showing an embodiment of a filter assemblyin position on a valve assembly.

[0015]FIG. 5 is a cross-sectional view showing an embodiment of a filterassembly mated with a valve assembly.

[0016]FIG. 6 is a perspective view showing another embodiment of theinvention.

DETAILED DESCRIPTION

[0017] In the drawings that accompany this description, the samenumbered elements shown in separate figures are intended to representsimilar elements. The embodiment of the filter assembly shown in theaccompanying drawings is intended to be fitted against an existingone-way valve in an existing collapsible, evacuable container. Thiscontainer is known as a SPACE BAG, and is manufactured by NEW WESTPRODUCTS, INC. of Redwood City, Calif. Those skilled in the art willappreciate that embodiments of the filter assembly may be adapted foruse with a wide variety of one-way valves and containers.

[0018]FIG. 1 is a perspective view of an embodiment of the invention. Anevacuable container 2 includes a bag 4, a valve assembly 6, and a seal8. During use, one or more discrete articles or a bulk material may beplaced in bag 4, after which bag 4 is sealed using seal 8. Air is drawnout of bag 4 through valve assembly 6 using a conventional vacuumsource, such as a household or industrial vacuum cleaner. Valve assembly6 and seal 8 maintain the vacuum inside bag 4 when the vacuum source isremoved. Details regarding embodiments of valve assembly 6 are discussedin U.S. Pat. No. 5,480,030, mentioned above, and also in applicationSer. No. 08/851,361 incorporated herein by reference in its entirety.Additional embodiments of valve assembly 6 are discussed below and shownin the accompanying drawings. In one embodiment, seal 8 is aninterlocking air tight Zipper-type fastener manufactured byMinigrip/Zip-Pak (An ITW Company) of Mission Viejo, Calif.

[0019]FIG. 2 illustrates an embodiment of bag 4. Bag 4 has a hole 10 inwhich to install valve assembly 6, and an opening 12 through whicharticles or bulk material may be placed for storage. Details regardingembodiments of bag 4 are discussed in U.S. Pat. No. 5,480,030, mentionedabove. In one embodiment the bag is constructed of a blended extrusionlayer of polyethylene sandwiched between a nylon layer and a layer ofpolyethylene sheeting. In some embodiments materials comprising the bagmay be altered so as to prevent interaction with the bag contents. Sucha custom bag composition is based on user need and may be determinedusing material qualities known in the art or by experimentation.

[0020]FIG. 3 is an exploded perspective view showing valve assembly 6and filter assembly 14. As shown, valve assembly 6 is comprised of abase 16, a retaining ring 18, and a valve element 20. Valve assembly 6is mounted to bag 4 (FIGS. 1 and 2) such that flange 17 of base 16 is onthe inside of bag 4. Base 16 extends through hole 10 and is held inplace by retaining ring 18 placed over base 16 on the outside of bag 4.

[0021] Valve element 20 provides the one-way feature in valve assembly6. In the embodiment shown, valve element 20 is made of conventionalclear polyvinylchloride (PVC). Valve element 20 has an outer annularportion 22 and an inner diaphragm 24. Annular portion 22 functions as aface against which a vacuum source, such as a conventional household orindustrial vacuum cleaner nozzle (FIG. 6), may be sealed as the nozzleis pressed against base 16. When the nozzle is in place and a vacuumpressure draws air through the nozzle, diaphragm 24 flexes open and airpasses through a plurality of holes 26 in base 16. When the nozzle isremoved, diaphragm 24 returns to its original shape and seals againstbase 16, thus preventing air from passing back through holes 26.

[0022] As shown, a plurality of radial vanes 28 separate holes 26. Vanes28 hold a central valve element support 29. Thus each of holes 26 isformed as the open space bounded by recessed portion 16B of base 16, twoeach of vanes 28, and valve element support 29. FIG. 5 provides anotherview of holes 26. As shown, vanes 28, spaced around support 29, areseparated by holes 26.

[0023] Referring again to FIG. 3, filter assembly 14 fits against valveassembly 6. Filter assembly 14 is comprised of a top portion 30 and acylindrical sidewall 32. Other embodiments may have different sidewallshapes, the sidewall being adapted for use with a particular valve base.As shown, filter assembly 14 fits against base 16 to form a seal tightenough to keep any material stored in bag 4 from passing into valveassembly 6. In some embodiments this seal may be air-tight. A pluralityof slots 34 in filter sidewall 32 are configured to fit over respectivevanes 28 in base 16. A raised annular lip 36 fits against base 16'sinner wall 38. Details of the fit between filter assembly 14 and base 16are discussed in detail below.

[0024] Filter assembly 14 has a plurality of openings 40 through whichair passes while being drawn through valve assembly 6. As shown,openings 40 are arranged in a series of fan-shaped patterns havingcurved slots. Other embodiments of filter assembly 14 may use differentshapes and patterns for openings 40. A filter element 42, visible forexample through one of the openings 40, is placed underneath top portion30 and underlies openings 40 to prevent stored material from enteringvalve assembly 6.

[0025] In one embodiment, filter assembly 14 is made of conventionalpolyethylene. In another embodiment, filter assembly 14 may be made ofacrylonitrile-butadiene-styrene (ABS), known by trade names such asCYCOLAC or LUSTRAN. Some embodiments of the filter are injection molded.Other embodiments may be made using conventional fabrication methodssuch as milling. The material forming filter assembly 14 is soft, sothat a slight deformation occurs as filter assembly 14 is pressedagainst base 16, as described below. The deformation provides both aseal and friction by which filter assembly 14 stays in place.

[0026] In one embodiment of the invention, filter element 42 is a 47millimeter diameter, 0.02 micrometer PTFE membrane filter, supplied byPaul Gilman Laboratories of Fremont, Calif., as part S-66143, TF-200.The 47 mm filter element is then cut to slightly less than 1.34 inchesso as to fit within filter assembly 14. Embodiments of this inventionare not restricted to using this filter element type only, however, andother embodiments may use other filter element types. For example,filter element 42 may be optimized for a certain type of material to bestored within an evacuable container. User requirements may dictatefilter element 42 composition. Filter element 42 may be attached tofilter assembly 14 using various methods. For example, in oneembodiment, filter element 42 is attached to filter assembly 14 usingdirect heat transfer. In other embodiments, sonic welding or otheradhesive or connecting methods may be used. Filter assembly 14 may bepermanently attached to base 16, or filter assembly 14 may detachablefrom base 16 in order to, for example, permit filter element 42 to bereplaced.

[0027] As mentioned above, slots 34 are configured to fit over vanes 28.In some embodiments in which vanes are not used, however, slots 34 maybe omitted. In one embodiment, each slot 34 is 0.060±0.002 inch wide and0.47 inch long to ensure an adequate seal when filter assembly 14 ispressed onto base 16.

[0028] In the embodiment shown, a raised annular lip 36 is positionedaround the base of sidewall 32. This, lip 36 adds extra tension to thejunction of, and improves the seal between, sidewall 32 and base 16.Annular lip 34 provides an improved seal between filter assembly 14 andbase 16 over a seal between a straight edge junction of sidewall 32 andbase 16.

[0029]FIG. 4 is a plan view showing an embodiment of filter assembly 14mounted on an embodiment of base 16. As depicted, filter assembly 14fits over a plurality of radial vanes 28 (partially hidden by filterassembly 14) positioned on base 16.

[0030]FIG. 5 is a cross-sectional view showing an embodiment of valveassembly 6 mated with filter assembly 14, taken at cut line A-A in FIG.4. Valve base 16 is shown inserted through a flexible, air-tight bag 4and held in place by an annular retaining ring 18. An opening 50 isprovided in base 16 in which a nozzle (FIG. 6) from a vacuum source isplaced to draw air through the valve. In some embodiments, a removablecap (not shown) may be placed over opening 50 to protect inner portionsof valve assembly 6. A plurality of vanes 28 are positioned on theunderside of base 16.

[0031] Flexible diaphragm 24 is shown in position against a seat 52. Asdescribed above, when a vacuum source nozzle is placed into opening 50,vacuum pressure causes diaphragm 24 to flex and allow air, representedby arrow 54, to be drawn through valve assembly 6. When the vacuumsource nozzle is removed, diaphragm 24 returns to its position sealedagainst seat 52 so as to prevent air from flowing in a reverse directionthrough the valve. In the embodiment shown, diaphragm 24 and annularportion 22 are an integral piece, joined by two small bridge pieces(FIG. 3).

[0032] As mentioned above, further details regarding evacuablecontainers and one-way valves are given in U.S. Pat. No. 5,480,030, andin application Ser. No. 08/851,361.

[0033] Still referring to FIG. 5, filter assembly 14 is shown mated withvalve base 16. Lip 36 is shown sealing sidewall 32 against valve baseinner surface 38. As shown, filter assembly 14's sidewall bottom surface37 is shown sealed against base 16's surface 56, although in otherembodiments a slight gap is allowable due to the seal between lip 36 andsurface 38.

[0034] Also shown is a vane 28A extending through a slot 34 in filterassembly 14. It may be seen that the length of slot 34 should not exceedthe height of a vane 28, or else leakage may occur near the top junction58.

[0035] Filter element 42 is shown attached to the underside of filterassembly 14's top portion 30. Filter element 42 is positioned so thatair, represented by arrow 54, is filtered as it passes through each ofthe several air holes 40.

[0036]FIG. 6 is a perspective view showing an embodiment of theinvention during use. A container 70 is shown having a bag 4 placed in arigid vessel 71 to allow easier handling of a stored bulk material suchas a powder or granules. The rigid vessel should be strong enough tohold the desired bulk contents during routine handling. In someembodiments the rigid container may be a conventional container made ofplastic, corrugated fiber, bonded fiber, wood, or metal. In otherembodiments the container may be custom-fabricated to meet user needs.In some embodiments, the rigid vessel 71 may be omitted.

[0037] Stored material may be placed in bag 4 so as to fill vessel 71.As shown, however, a portion of stored bulk material has been removedfrom bag 4, illustrating the reusable nature of the evacuable container70. Bag 4 has been sealed with seal 8. A nozzle 72 from a vacuum source74 is placed, by hand for example, against valve assembly 6. Asdescribed above, vacuum source 74 draws air out from bag 4 through valveassembly 6. When sufficient air has been withdrawn from bag 4, nozzle 72is removed and both valve assembly 6 and seal 8 prevent air fromreentering bag 4. If at a later time an additional portion of materialstored in bag 4 is to be taken, seal 8 is opened, the material isremoved from bag 4, and then bag 4 is resealed and reevacuated asdescribed.

[0038] An advantage of embodiments of this invention is that it providesa reusable, evacuable container for granular or powdered bulk material.Such bulk materials may include items such as nylon resins, tea, cork,and foam products. Embodiments of the filter assembly prevent the bulkmaterial from entering and clogging both valve assembly 6 and the vacuumsource used to evacuate bag 4.

[0039] Another advantage of the embodiment shown and described is thatfilter assembly 14 may be removed and replaced with a fresh assembly ifthe filter element 42 becomes clogged. As shown in FIG. 6, a user opensseal 8 and reaches into bag 4 to remove and replace filter assembly 14.In other embodiments, however, filter assembly 14 may be permanentlyattached to, or formed as an integral part with, valve assembly 6.

We claim:
 1. A method of manufacturing a storage container, comprisingthe acts of: providing a flexible, air-tight bag having an opening forinserting material to be stored; providing an air-tight seal across theopening; providing a one-way valve assembly installed in the bag,wherein the valve assembly comprises a plurality of vanes and allows airto pass out of the bag but prevents air from entering the bag; andproviding a filter assembly shaped to mate with the valve assembly, tofit over the vanes, and to form a seal with the vanes, wherein thefilter assembly comprises at least one hole formed therein, and whereinthe filter assembly supports a filter element across the or each holesuch that air passing out of the bag through the valve assembly isfiltered.
 2. The method of claim 1, wherein the seal is resealable. 3.The method of claim 1, wherein the filter assembly is held against thevalve assembly by friction.
 4. The method of claim 1, wherein the filterassembly is made to be removable from the valve assembly so that asecond filter assembly may be mated with the valve assembly.
 5. Themethod of claim 1, wherein the filter assembly comprises: a cylindricalside wall having an outside surface and a first end; a top portionpositioned as a cap over the side wall at the first end; and a raisedannular lip positioned on the outside surface at an end opposite thefirst end, wherein the annular lip is configured to seal against asurface of the valve assembly.
 6. The method of claim 1 comprising theact of providing the valve assembly and the filter assembly as anintegral piece.
 7. The method of claim 1 comprising the act of providingthe filter element to prevent particles of a material stored in the bagfrom entering the valve assembly.
 8. The method of claim 1, wherein thefilter element comprises an about 0.02 micrometer filter.
 9. The methodof claim 1 comprising the act of providing a rigid vessel into whichvessel the bag is placed.
 10. The method of claim 1, wherein the one-wayvalve assembly is configured to receive a nozzle coupled to a vacuumsource.
 11. A method of manufacturing a storage container, comprisingthe acts of: providing a flexible, air-tight bag having an opening forinserting material to be stored; providing an air-tight seal across theopening; providing means for allowing air to pass out of the bag but notto pass into the bag, wherein the means for allowing air to pass out ofthe bag but not to pass into the bag comprises a plurality of vanes; andproviding means for filtering air passing out of the bag, wherein themeans for filtering air passing out of the bag comprises at least onehole formed therein, wherein the means for filtering air passing out ofthe bag supports means for filtering air passing through the or eachhole, and wherein the means for filtering air passing out of the bagcomprises a plurality of slots shaped to receive the vanes.
 12. Themethod of claim 11, wherein the seal is resealable.
 13. The method ofclaim 11, wherein the means for filtering air passing through the oreach hole is held by friction against the means for allowing air to passout of the bag but not to pass into the bag.
 14. The method of claim 11,wherein the means for filtering air passing out of the bag is made to beremovable from the means for allowing air to pass out of the bag but notinto the bag.
 15. The method of claim 11, wherein the means forfiltering air passing out of the bag prevents particles of a materialstored in the bag from entering the means for allowing air to pass outof the bag but not to pass into the bag.
 16. The method of claim 11further comprising the act of providing means for rigidly supporting thebag.
 17. The method of claim 11, wherein the means for allowing air topass out of the bag but not to pass into the bag is configured toreceive means for coupling to a vacuum source.